428 PLANT DISEASES 



In the American form on R. nigrum the conidia are 

 larger, equal at both ends, 15-25 /x- long. An apparently 

 distinct var. or species. 



Gloeosporium venetum, Speg., Mich., i. p. 477. Spots 

 yellowish or ochraceous, small and rounded, or larger 

 and irregular towards the margin of the leaf, and sur- 

 rounded by a dusky purple line ; pustules minute, promi- 

 nent, solitary or gregarious ; conidia elliptico-cylindrical, 

 hyaline, contents granular and guttulate, 7-8X2-2-5 /x. 



On living leaves and stems of Rubus chamaeodorus and 

 R. idaeus. 



Distr. Europe, North America, Australia. 



Gloeosporium ampelophagum, Sacc., Mich., i. p. 217. 

 Spots or pustules subcircular, often confluent, blackening, 

 drying, and hardening the cortical strata of grape berries, 

 centre of spots greyish or rosy-primrose, due to the presence 

 of the extruded conidia ; pustules originating beneath the 

 epidermis, minute, densely gregarious, stroma thin, pul- 

 vinate, pallid, prosenchymatous, component cells minute, 

 the superficial ones shortly apiculate and bearing the 

 conidia; conidia oblong, ellipsoid or ovate, 5-6x3*5 ft, 

 2-guttulate, hyaline. 



Gloeosporium fructigenum, Berk., Card. Chron., 1856, p. 

 245. Pustules concentric, dingy rose- red, erumpent through 

 a simple or laciniate pore, pulvinate; conidia oblong or 

 cylindrical, often curved, 20-30 x 5-6 /z, hyaline ; basidia 

 subequal in length, simple, rarely furcate, continuous. 



Gloeosporium musarum, Cke. and Mass., Grev., xvi. 

 p. 3. Pustules innate, erumpent, gregarious, with a rosy 

 tinge; conidia elongate ellipsoid, ends rounded, continu- 

 ous, hyaline, 10-12X4-5 A* contents granular. 



